Background and Objective: Several studies have shown an association between daily variation in the nitrogen dioxide (NO2) concentration and daily deaths. Given this growing evidence, we investigated whether particular conditions may increase the individual susceptibility to this pollutant. We investigated the NO2-mortality relationship, for specific causes of death, considering individual socio-demographic features and chronic or acute medical conditions as potential effect modifiers. Methods: We studied 271,111 subjects aged over 35 years, resident in 10 Italian cities and deceased from natural causes between 2001 and 2005. A time-stratified case-crossover analysis was chosen to evaluate the short term effects of NO2 on natural, respiratory and cardiac mortality at different lags (from 0 to 5 and cumulative). To study susceptibility factors individual information on socio-demographic features and hospital admissions in the previous two years was collected via record-linkage Results: For an increase of 10 mg/m3 NO2, we found a statistically significant excess risk for natural mortality of 2.09% (lag 0-5, 95CI% = 0.96;3.24), 2.63% for cardiac mortality (lag 0-5, 95CI% = 1.53;3.75) and 3.48% for respiratory mortality (lag 1-5, 95CI% = 0.75;6.29). These effects were independent from those of PM10. Greater effects on total mortality were estimated among people aged 85 and over (3.41%) with a clear effect modification for subjects with at least one hospital admission in the two years preceding the death (2.86%) and for subjects who had three or more specific chronic conditions (3.62%). Changes in pulmonary circulation and heart conduction disorders were the conditions that conferred the highest susceptibility. Conclusion: Strong and homogeneous increased risks of mortality for exposure to current levels of NO2 were detected, with prolonged effects. Higher susceptibility was found for the elderly and for subgroups of the population characterized by specific chronic conditions
SHORT TERM EFFECTS OF NITROGEN DIOXIDE EXPOSURE ON MORTALITY AND SUSCEPTIBILITY FACTORS
VIGOTTI, MARIA ANGELA;
2009-01-01
Abstract
Background and Objective: Several studies have shown an association between daily variation in the nitrogen dioxide (NO2) concentration and daily deaths. Given this growing evidence, we investigated whether particular conditions may increase the individual susceptibility to this pollutant. We investigated the NO2-mortality relationship, for specific causes of death, considering individual socio-demographic features and chronic or acute medical conditions as potential effect modifiers. Methods: We studied 271,111 subjects aged over 35 years, resident in 10 Italian cities and deceased from natural causes between 2001 and 2005. A time-stratified case-crossover analysis was chosen to evaluate the short term effects of NO2 on natural, respiratory and cardiac mortality at different lags (from 0 to 5 and cumulative). To study susceptibility factors individual information on socio-demographic features and hospital admissions in the previous two years was collected via record-linkage Results: For an increase of 10 mg/m3 NO2, we found a statistically significant excess risk for natural mortality of 2.09% (lag 0-5, 95CI% = 0.96;3.24), 2.63% for cardiac mortality (lag 0-5, 95CI% = 1.53;3.75) and 3.48% for respiratory mortality (lag 1-5, 95CI% = 0.75;6.29). These effects were independent from those of PM10. Greater effects on total mortality were estimated among people aged 85 and over (3.41%) with a clear effect modification for subjects with at least one hospital admission in the two years preceding the death (2.86%) and for subjects who had three or more specific chronic conditions (3.62%). Changes in pulmonary circulation and heart conduction disorders were the conditions that conferred the highest susceptibility. Conclusion: Strong and homogeneous increased risks of mortality for exposure to current levels of NO2 were detected, with prolonged effects. Higher susceptibility was found for the elderly and for subgroups of the population characterized by specific chronic conditionsI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
